Large Slowly Changing Dimension

Hello,
I'm somewhat new to data warehousing, and have some basic questions.
Let's say I have a fact table, named sales. The financial analyst
would like to be able to sort the sales information based on several
customer related attributes. Some of these attributes would include
zip code, age, and income. While I can create a customer dimension,
these attributes change over time.
The analysts are really only interested in these customer attributes
at the time of the sale. For example, they only care about where a
customer lived at the time of the sale, but not where they are living
now. Now I know there are different techniques for dealing with
changing dimensions, but I'm left with the impression that it would be
making things more complicated then necessary.
Would it not be best to just simply store this information in the
fact table itself? While I'm aware that fact tables are primarily used
to store numerical information, I don't see the advantage of putting
this information in a separate dimension.
Your input would be much appreciated.
Thanks,
AttilaHi,
You say the analysts are interested in the customer attributes at the time
of the sale. So these attributes will have to be stored in dimensions to be
able to analyse them using datawarehouse techniques. These must be slowly
changing. So when you add more salesfacts, e.g. with a zipcode that doesnt
exist in the zipcode dimension yet, you'll have to add it to the dimension.
The alternative is to drop and recreate all the facts and dimensions, but
that's no option if the customers move or the incomes change in the source
system.
Good luck...
Jeroen.
"Attila" <ThisIsAFakeAddress35@.hotmail.com> wrote in message
news:9516751f.0401290847.23e49471@.posting.google.com...

quote:

---

> Hello,
> I'm somewhat new to data warehousing, and have some basic questions.
> Let's say I have a fact table, named sales. The financial analyst
> would like to be able to sort the sales information based on several
> customer related attributes. Some of these attributes would include
> zip code, age, and income. While I can create a customer dimension,
> these attributes change over time.
> The analysts are really only interested in these customer attributes
> at the time of the sale. For example, they only care about where a
> customer lived at the time of the sale, but not where they are living
> now. Now I know there are different techniques for dealing with
> changing dimensions, but I'm left with the impression that it would be
> making things more complicated then necessary.
> Would it not be best to just simply store this information in the
> fact table itself? While I'm aware that fact tables are primarily used
> to store numerical information, I don't see the advantage of putting
> this information in a separate dimension.
> Your input would be much appreciated.
> Thanks,
> Attila

---

|||> So these attributes will have to be stored in dimensions to be
able to analyse them using datawarehouse techniques.
Can you elaborate on this part? What specifically will an analyst not
be able to do if I store the customer data in the fact table?
Thanks,
Attila
"Spike" <jeroenaNOSPAM@.hotmail.com> wrote in message news:<bvgf14$sjl$1@.reader08.wxs.nl>...[QUOTE]
> Hi,
> You say the analysts are interested in the customer attributes at the time
> of the sale. So these attributes will have to be stored in dimensions to b
e
> able to analyse them using datawarehouse techniques. These must be slowly
> changing. So when you add more salesfacts, e.g. with a zipcode that doesnt
> exist in the zipcode dimension yet, you'll have to add it to the dimension
.
> The alternative is to drop and recreate all the facts and dimensions, but
> that's no option if the customers move or the incomes change in the source
> system.
> Good luck...
> Jeroen.
> "Attila" <ThisIsAFakeAddress35@.hotmail.com> wrote in message
> news:9516751f.0401290847.23e49471@.posting.google.com...|||I suggest reading articles written by Ralph Kimball. Here's one of his
classic articles on slowly changing dimensions.
http://www.dbmsmag.com/9604d05.html
"Attila" <ThisIsAFakeAddress35@.hotmail.com> wrote in message
news:9516751f.0402020643.36d448b7@.posting.google.com...
> able to analyse them using datawarehouse techniques.
> Can you elaborate on this part? What specifically will an analyst not
> be able to do if I store the customer data in the fact table?
> Thanks,
> Attila
>
> "Spike" <jeroenaNOSPAM@.hotmail.com> wrote in message
news:<bvgf14$sjl$1@.reader08.wxs.nl>...
time
be
slowly
doesnt
dimension.
but
source|||There is an entire chapter in Ralph Kimballs book on mini dimensions,
which help to stabilise the pain of rapidly changing dimensions.
Ashish
On Tue, 17 Feb 2004 15:29:51 -0500, Domenico Discepola
<domenico_discepola@.quadrachemicals.com> wrote:

> I suggest reading articles written by Ralph Kimball. Here's one of his
> classic articles on slowly changing dimensions.
> http://www.dbmsmag.com/9604d05.html
>
> "Attila" <ThisIsAFakeAddress35@.hotmail.com> wrote in message
> news:9516751f.0402020643.36d448b7@.posting.google.com...
> news:<bvgf14$sjl$1@.reader08.wxs.nl>...
> time
> be
> slowly
> doesnt
> dimension.
> but
> source
>
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